IDENTIFICATION OF CHEMICAL REACTIONS

Objective: To identify an “unknown” solution based on it’s physical and chemical properties.

• Chemical reactions result in the formation of new substances (products) and the exchange of energy (heat, light)

• The formation of a gas or a precipitate indicates a chemical reaction

• A new substance might also be recognized by a change in color

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The Seven Known Solutions

Solution No. 1: hydrochloric acidSolution No. 2: sodium carbonateSolution No. 3: sodium hydroxideSolution No. 4: potassium chromateSolution No. 5: calcium chlorideSolution No. 6: sodium bisulfiteSolution No. 7: copper sulfate

LAB DIRECTIONS:

1. Mix every possible combination of the solutions using 2-3 drops of each in cavities in the Chemplate.

2. Record in the data table: gas, ppt., color, no rxn.

3. Get an unknown. Mix the unknown solution with each of the other solutions. Figure out what the unknown is by comparing with your data (HINT: it is one of the solutions you already tried).

OUTPUT

• Paste the data table into your IAN. (Record in data table: gas, ppt., color, no rxn.)

• Write a statement telling how you know what the unknown is: what reaction indications it had and with what other solutions, etc.

• Use color!

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